It depends on the person Babs, really hard to say. I always thought I got a ton from mine, but after some raw squats recently, my thoughts are changing. Also the weights they are using are not like a typical barbell so that will change things as well.

I suppose, it could act similar to a placebo in the form of a psychological safety net, due to the tightness of the briefs, the rebound which they know is available etc...even if there may be little to no carryover from the actual briefs.

A lot of weight lifted, either way; I was impressed when I saw it on TV.